EFFECTS OF TEMPERATURE AND LIGHT ON NITRATE CONTENT OF RADISH (RAPHANUS-SATIVUS L)

Research was carried out on the effect of temperature and irradiance on nitrate accumulation of a radish cultivar with a low nitrate content and another cultivar with a high one. Roots and leaves of plants grown continuously at a higher temperature or transferred for eleven days before harvest to higher temperatures had higher nitrate contents than plants at lower temperatures (18-degrees-C > 14-degrees-C > 10-degrees-C). Nitrate content increased when plants were placed in darkness three days before harvest. Clear difference in nitrate content occurred between the cultivars used, apart from when they were grown at 18-degrees-C.